Petition addressed to King Philip IV by Juan Espina: statement of Alfonso Martines de Laya.

Juan Espina claims to have made a “perfect vihuela or guitar” that can be played with the same speed and ease as a normal one with twelve frets.

Digo yo, Alfonso Martinez de Laya, que me obligo a tañer la guitarra o vihuela perfecta como la ha puesto don Juan de Espina Velasco, con la misma velocidad con que taño la falsa de doce trastos

corona1999, p. 42. “Juan Espina claimed that in the music in use the sizes of the intervals were not properly observed, and that there was a need for perfect instruments which divided the octave correctly, such as a "guitar" he had set up "scientifically", to which he had added all the necessary frets. To support his assertion, Espina added to the petition a statement by Alfonso Martinez de Laya, described as a "vihuela master" (maestro de vihuela), in which this musician undertook to play the new "perfect vihuela or guitar" instrument as well as the normal one.” This makes us suppose that he had constructed an instrument with frets for both sharps and flats in meantone temperament.